The present invention relates to a flooring composite which includes a shrink sheet floor covering layer (i.e., shrink flooring), and to a method for adhering the shrink flooring to a subflooring. Shrink flooring material has been used for a number of years in the construction of residential housing.
Shrink flooring has a number of advantages, including ease of installation, less subfloor preparation than other types of flooring materials, and high flexibility.
The mechanism by which shrink flooring works is well known and is a combination of the balance of the modulus of the top layer and the bottom layer of the flooring, and the stress-induced creep caused by rolling of the flooring prior to use. Before installing, the shrink flooring is rolled face out around a core, which is usually 4 inches in diameter or smaller. The top layer of the shrink flooring is thereby stretched. This stress causes creep, that is, molecular orientation to alleviate the applied stress. When the material is installed, the higher modulus of the top layer maintains the stretched length of the top layer and induces a stress in the bottom layer. The induced stress in the bottom layer then acts to reverse the creep in the top layer resulting in the product apparently shrinking. This shrinking occurs over a period of time after installation of the shrink flooring and gives the shrink flooring a number of advantages, including the ability to bridge smaller defects in the subflooring.
Heretofore, shrink flooring has been applied to subflooring by the use of staples or glue along the perimeter. The disadvantages of staples are that they cannot be used on a concrete floor, and that it may be difficult or impossible to staple under the toekicks of cabinets. The disadvantages of glue include the fact that it is messy, and that it has a limited working time, defined as the time during which the shrink flooring can be moved or adjusted in place after application of the glue. Other disadvantages of glue include increased waste, and finally, the solvents used in some glues are generally flammable.
There is thus a need in the art for a method of installing shrink flooring material which does not have the problems noted above inherent in the use of staples or glue. The present invention solves these problems through the use of a double-faced adhesive tape as described hereinafter.
The concept of opposing adhesive surfaces has been used in securing carpeting, as taught by U.S. Pat. No. 4,557,774. In this patent, a carpet pad positioned between a carpet and a floor surface has pressure-sensitive adhesive applied on its upper and lower surfaces.